--  @testpoint:opengauss关键字before(非保留)，作为函数名
--关键字不带引号-成功
drop function if exists before;
create function before(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--清理环境
drop function before;

--关键字带双引号-成功
drop function if exists "before";
create function "before"(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--清理环境
drop function "before";

--关键字带单引号-合理报错
drop function if exists 'before';
create function 'before'(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/

--关键字带反引号-合理报错
drop function if exists `before`;
create function `before`(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/